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(Myxiniformes: Myxinidae) in the Gulf of California, Mexico Hidrobiológica, Vol

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(Myxiniformes: Myxinidae) in the Gulf of California, Mexico Hidrobiológica, Vol Hidrobiológica ISSN: 0188-8897 [email protected] Universidad Autónoma Metropolitana Unidad Iztapalapa México Hendrickx, Michel E.; Hastings, Philip A. Ecological data for Myxine circifrons Garman, 1899 (Myxiniformes: Myxinidae) in the gulf of California, Mexico Hidrobiológica, vol. 17, núm. 3, 2007, pp. 273-276 Universidad Autónoma Metropolitana Unidad Iztapalapa Distrito Federal, México Available in: http://www.redalyc.org/articulo.oa?id=57817309 How to cite Complete issue Scientific Information System More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative Hidrobiológica 2007, 17 (3): 273-276. NOTAS Diciembre 2007 Ecological data for Myxine circifrons Garman, 1899 (Myxiniformes: Myxinidae) in the gulf of California, Mexico Información ecológica de Myxine circifrons Garman, 1899 (Myxiniformes: Myxinidae) en el golfo de California, México 1Michel E. Hendrickx and 2Philip A. Hastings (1) Unidad Académica Mazatlán, Laboratorio de Invertebrados Bentónicos, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, P. O. Box 811, Mazatlán, 82000, Sinaloa : [email protected]) (2) Marine Biology Research Division, Scripps Institution of Oceanography, University of California San Diego, 9500 Gilman Dr., La Jolla, CA 92093-0208 Hendrickx M. E. and P. A. Hastings. 2007. Ecological data for Myxine circifrons Garman, 1899 (Myxiniformes: Myxinidae) in the gulf of California, Mexico. Hidrobiológica 17 (3): 273-276 Abstract. Specimens of the hagfish Myxine circifrons Garman, indicando así que la competencia entre éstos y los camarones 1899, were captured in traps in three sampling stations in the pudo impedir que estos últimos entraran en la trampa. southern gulf of California, Mexico. There was no clear relation Palabras clave: Myxine circifrons, Myxiniformes, golfo de California, between oxygen concentration and hagfish abundance. This México, nuevos registros. species appears to be tolerant of moderate (0.28-0.6 ml/l) hypoxia. Other species collected in the traps include Pandalus Hagfishes include approximately 70 species of jawless, amplus (Bate, 1888) and Heterocarpus affinis Faxon, 1893, two eel-like chordates that are typically associated with muddy subs- relatively large species of Pandalidae, and Lebbeus scrippsi trates and found in marine waters from a few meters to at least Wicksten and Méndez, 1982, a small-size Hippolytidae shrimp. 2,700 m depth (Mincarone, 2001; Nelson, 2006). Their potential Capture of pandalids was low when hagfish were abundant, thus importance in marine communities is indicated by their often high indicating that competition between the fish and shrimps might biomass that has been estimated at over 8,000 kg km-2 for Myxine prevent the latter to enter the trap. glutinosa Linnaeus, 1758 in the gulf of Maine (Martini et al., 1997). Keywords: Myxine circifrons, Myxiniformes, gulf of California, Increasing demand for hagfish skin in the South Korean market Mexico, new records. has brought increased pressure on the hagfish fishery in Canada and the USA, and revenues reached ca $100 million US in 1990 for Resumen. Especimenes de mixínas (peces brujas), Myxine this Asian country (Gorbman et al., 1990; Grey et al., 2006). circifrons Garman, 1899, fueron capturados con trampas en tres estaciones de muestreo en el golfo de California, México. No se During a survey in the SE gulf of California to evaluate observó una relación clara entre la concentración de oxígeno the potential of benthic traps to capture the caridean shrimp y la abundancia de los especímenes. La especie parece ser Heterocarpus affinis Faxon, 1893, a commercially interesting tolerante a un ambiente moderadamente hipóxico (0.28-0.6 species that had been collected previously in the area using a ml/L). Otras especies recolectadas con las trampas incluyeron benthic sledge (see Hendrickx, 2004), the hagfish Myxine circi- los crustáceos Pandalus amplus (Bate, 1888) y Heterocarpus affinis frons Garman, 1899 was caught in approximately 75% of the traps. Faxon, 1893, dos especies relativamente grandes de Pandalidae The genus Myxine includes 22 species of hagfishes, of which six y a Lebbeus scrippsi Wicksten y Méndez, 1982, un camarón have been recorded in the East Pacific (Wisner & McMillan, 1995; Hippolytidae de tamaño pequeño. La captura de pandálidos en Mincarone, 2001; Møller et al., 2005). Two of these are found in las trampas fue baja cuando los peces bruja eran abundantes, the northern hemisphere of the East Pacific: M. circifrons and M. 274 Notas hubbsi (Wisner & McMillan, 1995). Herein we report on the abun- 108o21.86’W), 1150 m, trap 1: 7 specimens (TL 312-455 mm); dance of M. circifrons and some environmental data measured Station 2 (24o51.33’N, 108o57.37’W), 850 m: trap 1, 17 specimens during this survey. (TL 395-472 mm), trap 2, 6 specimens (TL 378-450 mm); Station 3 (25o40.83’N, 109o54.38’W), 1435 m: trap 1, 16 specimens (TL A small series of deep-water traps (three at each station) 330-452 mm), trap 2, 6 specimens (TL 350-435 mm), trap 3, 17 were deployed in three field stations in April 2002 during the specimens (TL 360-471 mm). PANDAL Cruise to the gulf of California, Mexico by the R/V “El Puma” of the Instituto de Ciencias del Mar y Limnología, UNAM, The number of specimens captured per trap varied con- using an anchor attached to 1.2 cm tick polyethylene cable and a siderably, from none (St. 1, two traps with no hagfish) to 17 double buoys system (King, 1987). Fish-heads were used as bait. specimens. Catch per station estimated for a standard 24-hour Traps remained on the bottom for different periods of time due period was 3.9 specimens (St. 1), 9.2 (St. 3) and 31.3 specimens to navigation time restrictions. At each station, a CTD-O2 probe (St. 2) (Table 1). Dissolved oxygen measured close to the bottom (Seabird SBE probe) attached to a Rosette sampler was submer- level does not indicate any clear relation between oxygen con- ged to approximately 10 m above the bottom; water samples were centration and hagfish abundance. Thus this species, like other simultaneously collected with opening-closing bottles. Dissolved hagfishes (e.g., Hansen & Sidell, 1983) appears to be tolerant of oxygen content was measured using duplicate samples following moderate (0.28-0.6 ml/L) hypoxia, but was also found in water the Winkler method. Fish specimens were preserved onboard, with a higher oxygen concentration (St. 3, 1.15 ml/L). The oxygen measured in the laboratory (TL, total length ± 0.5 mm), and concentrations measured in the sampling area correspond well identified using the key in Wisner and McMillan (1995). Voucher with previous records in the region, with a remarkable increase material (SIO 05-83; ICMYL-353.01) was deposited at the Scripps starting at depth > 700-800 m after an almost anoxic zone (MOZ, Institution of Oceanography Marine Vertebrate Collection and the Minimum Oxygen Zone) that extended roughly from 150 to 750 fish collection of the Unidad Académica Mazatlán, in Mazatlan, m (Hendrickx, 2001). Epibenthic water temperatures (from 3.0 Mexico. to 5.3o C) were in agreement with standard depth distribution of water masses between 850 and 1,435 m in the SE gulf of California A total of 69 specimens of adult Myxine circifrons were (Alvarez-Borrego, 1983). captured in the 9 samples (3 traps at each of 3 stations). The smallest specimen was 312 mm TL and the largest 471 mm. Only a few other species were collected in the traps, inclu- Most specimens were found inside traps, but a few were found ding Pandalus amplus (Bate, 1888) and H. affinis, two relatively attached to the external walls when the traps were retrieved large species of Pandalidae with potentially high commercial on deck. Collection details are as follows. Station 1 (24o17.36’N, market value (Holthuis, 1980; Hendrickx & Wicksten, 1989). The Table 1. Sampling stations where traps were deployed, duration of sampling, and environmental parameters measured at the epibenthic level. Dh, duration in hours; TS, total number of hagfish specimens in all three traps; C/24, catch per 24 hours; Dm, depth in meters; T (oC), epibenthic temperature; O2 (ml/l), epibenthic oxygen concentration. St. Deployment time (hour/date) Recovering time (hour/date) Dh TS C/24 Dm T O2 1 22:30 / 02 April 17:30 / 04 April 43 7 3.9 1,150 3.9 0.60 2 06:00 / 03 April 12:30 / 04 April 30 23 31.3 850 5.3 0.28 3 14:00 / 03 April 05:00 / 04 April 15 39 9.2 1,435 3.0 1.15 Table 2. Previous records for Myxine circifrons in the Gulf of California based on material held at the Scripps Institution of Oceanography (Wisner and McMillan, 1995) (Fig. 1, open circles). Collection voucher Locality Depth (m) Number (Size Range mm) SIO 68-59 23o07’N, 1 09o19’W 1,280 25 (133-510) SIO 68-60 23o07’N, 109o11’W 1,830 6 (365-496) SIO 68-118 25o37’N, 109o43’W 1,190 110 (125-490) SIO 68-119 25o36’N, 109o45’W 1,490 25 (280-475) Hidrobiológica Notas 275 third species that incidentally appeared in the traps was Lebbeus 1,190 and 1,830 m depth (Table 2). Depth records obtained during scrippsi Wicksten and Méndez, 1982, a small-size Hippolytidae this survey correspond to the known range. Myxine hubbsi, the shrimp. Capture of pandalids were low when hagfish were second eastern Pacific species of the genus recorded in the abundant, thus indicating that the presence of the fish on the northern hemisphere, is known from 33o N to 34o S, including two trap walls might prevent the shrimp from gaining access to the localities near Cabo San Lucas, Mexico, close to the western entrance and the bait.
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